1. Field of the Invention
The present invention relates to a sewing machine having an upper feed, wherein an upper feed halting mechanism is provided to enable halting of a mechanism which drives the upper feed teeth, when the upper feed is not used.
2. Description of the Related Art
Cloth feed for feeding the cloth that is the object of sewing in accordance with a sewing action is normally performed by lower feed teeth, but upper/lower-feed sewing machines are known, in which upper feed teeth are also provided additionally and upper and lower feed is performed by supporting the sewing object from above and below.
However, the upper feed teeth may be necessary or may be unnecessary, depending on the type of the sewing object. If the upper feed teeth are not necessary, then the upper feed teeth are removed from the installation location or are withdrawn from the prescribed position. There is a drawback in that the replacement work in this case is burdensome.
There are also machines having a structure in which the upper feed teeth cannot be replaced due to the complexity involved in replacement, and there is a drawback in that only one type of feed teeth can be used, and the application thereof is limited. Furthermore, when the upper feed teeth are not used, it is necessary to withdraw the upper feed teeth to the rear of the sewing machine, and hence there are problems of safety and poorer usability, etc. Therefore, the present applicants have developed a sewing machine which simplifies the removal and replacement, etc. of the upper feed teeth. The contents thereof are shown in FIG. 7 as Japanese Patent Application Laid-open No. 2013-52122.
The contents of Japanese Patent Application Laid-open No. 2013-52122 is now described briefly. The description uses the same reference numerals for elements as those employed in Japanese Patent Application Laid-open No. 2013-52122, but the numerals are placed in parentheses in order to differentiate the elements from the description of the present invention. In the configuration of Japanese Patent Application Laid-open No. 2013-52122, a pressing bar (91), a pressing spring (92) and a needle mechanism (93) are provided in a machine main body (90), and a cloth pressing unit (α) provided with an upper feed mechanism (3) is installed on the lower end of the pressing bar (91).
An upper feed drive mechanism (β) for driving the upper feed mechanism (3) is installed on the pressing bar (91), and the upper feed mechanism (3) is driven in coupled fashion with the upper feed mechanism (3) in the coupling section (5). The upper feed mechanism (3) performs an upper feed movement by this driving, and performs an operation for feeding cloth which is the sewing object in the direction of the arrow. The cloth pressing unit (α) can be installed on and uninstalled from the pressing bar (91). The cloth pressing unit (α) is installed on the pressing bar (91) and is coupled with the upper feed drive mechanism (β) in the coupling section (5). Thereby, the upper feed mechanism (3) is driven.